Worktable and relieving mechanism for grinding machines



E. A. WALKER 1,895,830

.WORKTABLE AND RELIEVING MECHANISM FOR GRINDiNG MACHINES Jan. 317% Filed March. 19, 1951 e Sheets-Sheet 1 E. A. WALKER Jan. 31, 1933.

WORKTABLE AND RELIEVING MECHANISM FOR GRINDING MACHINES 6 Sheets- Sheet 2 Filed March 19, 1951 1933- E. A. WALKER 1,895,830

WORKTABLE AND RELIEVING MECHANISM FOR GRINDING MACHINES Filed March 19, 1931 6 Sheets-Sheet 3 E. A. WALKER 1,895,830

WORKTABLE AND RELIEVING MECHANISM FOR GRINDING. MACHINES Jan. 31, 1933.

6 Sheets-Sheet 4 E. A. WALKER Jan .31, 1933.

WORKTABLE AND RELIEVING MECHANISM FOR GRINDING MACHINES Filed March 19,. 1951 6 Sheets-Sheet 5 Jan. 31, 1933 E. A. WALKER 1,895,330

WORKTABLE AND YRELIEVING MECHANISM FOR GRINDIUNG MACHINES F iled March 19, 1951 SSheets-Sheet 6 Patented Jan. 31, 1933 UNITED STATES PATENT OFFICE ERNEST A. WALKER, OF WORCESTER, MASSACHUSETTS, ASSIGNOR TO JOHN BATH, OT

: WORCESTER, MASSACHUSETTS WORKTABLE AND RELIEVING MECHANISM FOR GRINDING MACHINES Application filed March 19, 1931. Serial No. 523,802.

This invention relates to machines for external grinding, in which the work is mounted on a work slide or table and in which the 7 work table is reciprocated relative to the grinding wheel.

It is the general object of my invention to provide improved mechanism for relievingthe teeth of a tap mounted on such a reciprocating work table by oscillating the work toward and from the grinding wheel in timed relation to therotation of the work. The machine is particularly adapted for relieving the teeth of unusually long taps or other s milar work.

A further object of the invention is to provide an improved and more direct drive for the Work and for the relieving mechanism when these parts are mounted on a reciprocating work table.

An important feature of the invention relates to the provision of an improved twopart table construction.

My invention further relates to arrangements and combinations of parts which will be hereinafter described and more particularly pointed out in the appended claims.

A preferred form of the invention is shown in the drawings, in which Fig. 1 is a plan view of parts of a grindin;}; machine embodying my improvements;

Fig. 2 is a sectional end elevation, taken along the line 2-2 of Fig. 1;

Fig. 3 is a partial sectional end elevation, taken along the line 330f Fig. 1;

Fig. 4 is a front elevation, partly in section, of the head stock and relieving mechanism, looking in the direction of the arrow 4 in Fig. 1;

Fig. 5 is a detail sectional side elevation, taken substantially along the line 55 in Fig. 1;

Fig. 6 is a partial sectional end elevation, taken along the line 66 in Fig. 5;

Fig. 7 is a plan view of a swivel table;

Fig. 8 is a plan view of a rocking table which is pivotally mounted on the swivel table;

Figs. 9 and 10 are end elevations of the swivel and rocking tables, looking in the directions of the arrows 9 and 10 in Figs. 7 and 8 respectively;

Fig. 11 is an end elevation of a portion of the head stock;

Fig. 12 is an end view of a cam roll stand;

Fig. 13 is a sectional end elevation, taken along the line lit-13 in Fig. 7 and showing the pivot connection of the swivel'table to the'work slide;

Fig. 14 is a side elevation, partly in section, of the tail stock with a piece of work supported therein;

Fig. 15 is a partial end elevation showing a modified construction;

Fig. 16 is a partial front elevation, looking in the direction of the arrow 16in Fig. 15;

Fig. 17 is a side elevation of a wheel truing device;

Fig. 18 is a partial plan view, showing the work supported upon centers, and

Fig. 19 is a diagrammatic view showing the lay-out ofone of the relieving cams.

Referring to the drawings, I have shown 2.

reciprocating the work slide forming no part of my present invention.

A swivel table 24 (Figs. 7 and 13) is supported on the work table 22 and is angularly adjustable thereon about theaxis of a pivot stud 25 (Fig. 13) seated in the work slide 22 and extending upward into a recess 26 in the under side of the swivel table 24. Segmental slots 27 (Fig 7) are formed in the ends of the swivel table 24 to receive clampingbolts 28 (Fig. 1) by which the swivel table may be secured to the work slide. Graduations 29 at the left hand end of the work table cooperate with an index line 30 (Fig. 1) to indicate the angular position of the swivel table.

An adjustin screw 31 (Fig. 1) ma mounted in a %e be aring 32 on'the end 0 the work slide 22 and is threaded into a sleeve or nut 33, swiveled to the end of a bracket 34 bolted to the swivel table 24.

A rocking table 36 (Figs. 8 and 10) is provided with spaced bearing portions 37 adapted to fit' closely between corresponding bearing portions 38 on the swivel table 24. -A rock shaft 40 (Fig. 2) extends through the bearing portions 37 and 38 and forms a pivotal connection between the rocking table 36 and the swivel table 24.

The rockin table 36 is provided with guiding surfaces or a head stock 42 (Figs. 2 and 11) and a tail stock 43. The rocking table 36 is also provided with a T slot 44 to receive the heads of clamping bolts 45 by which the head and tail stocks may be secured in longitudinally adjusted position.

The head stock 42 is provided with bearin s 47 and 48 (Fig. 5) for a hollow work spind e 50 on which a work-holding chuck 51 (Fig. 4) may be mounted, or in which a work center 52 (Fig. 18) may be secured. When the work center is used, a driving plate 53 and dog 54 may replace the chuck 51. The chuck may be of any usual or commercial construction but preferably has an axial opening permitting long work to extend therethrough, as indicate in Fig. 14. a],

A worm gear 56 (Figs. 5 and 6) -1S freely rotatable on the work spindle 50 and is continuously rotated by a worm 58 meshing therewith and mounted on a short shaft 59 (Fig.6) which is directly connected by a coupling 60 to a flexible driving shaft 61 (Fig. 1).

A cone clutch member 63 (Fig. 5) is keyed to the work spindle50 and is adapted to be moved yieldingly axially by a spring 64 to engage the conical outer surface of a flange 65 on the side of the, worm gear 56. The clutch member 63 has an annular groove or recess 66 to receive the ends of a forked arm or yoke 67 pivoted at 68 and connected to an arm '69 having a recess 70 to receive an eccentric 71 on a rock shaft 72. The shaft 72 is provided with a handle 73 by which the shaft and eccentric may be turned to advance or withdraw the clutch member 63 and thus control the driving connection between the worm gear 56 and the work spindle 50. The use of the flexible drive shaft 61 permits the work table to be reciprocated and the table 36 to rock about the axis of the shaft 40 without interfering with the driving connections.

The tail stock 43 may be provided with the ordinary tail center 75, as shown in Fig. 18, or may be rovided with a freely rotatable sleeve 76 (Fig. '14) on which a chuck 77 may be mounted. The sleeve and chuck prefer ably have axial openings to permit the end of a long tap or other piece of work W to extend therethrough and to be secured and centered by the clutch 77.

84 and is connected through .anintermediate gear 89 (Fig. 3) to a gear 90 (Figs. 4 and 5) keyed to the work spindle 50.

The intermediate gear 89' is pivoted on a stud 92 (Fig. 3) secured in a segmental slot 93 in a gear plate 94, pivoted at 95 to the head stock 42 and also secured to the head stock by a bolt 96 extending through a slot 97 in the upper end of the gear plate 94. The gears 88, 89 and 90 constitute change gears for which others may be substituted to produce any desired speed relation between the work -spindle 50 and the cam shaft 84. This speed relation will depend upon the number of lands of the tap to be relieved and also upon the number of risers or high spots on the cam 82. I

In Fig. 19 I have diagrammatically indicated the work V as having four lands an the cain 82 as having a high spot 100 in each quarter of its periphery, the high spots thus correspondin in number tothe lands of the tap. With the work and cam thus related, the gears .88, 89 and 90' would be selected to rotate the work and the cams in unison.

It will be noted'that a dwell 101 is pref-- erably provided at the low spot of the cam, which corresponds-to the largest diameter or cutting edge of the tap. The teeth may be left full size for'any desired an 1e by varying the amount of the dwell. etween the alternate dwells and high spots, the cam surfaces preferably increase and decrease gradually in diameter, thus giving a smooth and easy motion 'to the oscillating table and the work mounted thereon.

A number of cams 82 are rovided in which the throw of the camor t e extent of dwell may be varied. The cam roll stand 80 may be adjusted lengthwise in a T slot 102 (Fig.2) in the swiveltable 24 to bring the roll 81 under any selected cam 82.

It will be noted that the rocking table is supported throughout its length on the rocking shaftv 40, which in turn is fully supported upon the swivel table 24, thus affording .a long and extended rocking bearing between the tables 24 and 36.

vIn Figs. 15 and 16 I have shown an additional device by the use of which the grinding machine may be 'used for indexing instead of relieving the work. For this purpose the change gear 90 is removed from the work spindle 50 and the disc 110 (Figs. 15

An index pin 120 is mounted on a spring plunger 121 in one end of a lever 122. The lever 122 is pivoted on a stud 123 in the head stock 42 and the opposite endof the lever is provided with a spring-plunger 125 adapted to enter in one of a series of holes 126 in a rearward projection 127 of the head stock 42.

By placing the stud 125 in difi'er'ent openings 126, the index pin 120 may be brought into alignment with different circles of holes in the disc 110. Taps or other work may be indexed by this device for any desired number of subdivisions from one to eight. Obviously additional circles containing other members of holes may be added if desired.

\Vhen the machine is to be used for indexing or for producing ordinary cylindrical work, the cam roll 81 may be removed or may be moved out of alignment with any one of the cams,82, in which event shoulders 140 (Fig. 10) on the rocking table 36 will engage stop pins 141 (Fig. 9) on the swivel table 24 to maintainthe rocking table in a predetermined position.

Springs 142 (Fig. 2) are seated in recesses 143 in the under side of the swivel table 24 and bolts 145 extend upward through the springs into the under side of the rocking table 36. The springs 142 act to seat one of the cams 82 firmly 'on the cam roll 81 or to seat the rocking table firmly on the stop pins 141.

In Fig. 17 I have shown a simple wheel truing device comprising a diamond holder 130 axially adjustable in a post 131, which in turn may be adjusted angularly or axially in a sleeve 132 projecting upward from a stand 133 mounted to slide along the guideways of the rocking table 36 and to be secured thereto by a clamping bolt 135. By thus mounting the truing device on the rocking table which supports the work, it is possible to true the wheel at an exact radial distance from the centers on which the work is rotated.

From the foregoing description it will appear that I have provided relieving mechanism so designed that it may be applied to a grinding machine in which the wheel table and work are reciprocated relative to the grinding wheel and also in which the work may rotate about an axis at an angle to the" path of travel of the wheel slide on the machine bed. 1

I have also provided a construction by which the extent of relieving action can be quickly and easily adjusted and I have provided means for driving the relieving cams in any desired speed relation to the rotation of the .work.

While I have shown my improved mechanism as embodying a swivel table, it will be understood that the invention retains many advantages when the swiveling of the table 24 is omitted. In such cases the table 24 may be formed integral with or may be secured in fixed relation to the wheel slide 22.

In the claims, it will be understood that the term work slide. includes the swivel table or its equivalent as a part thereof when the swivel table is not intended as a separate element in the claims.

Having thus described my invention and the advantages thereof, I do not wish to be limited to the details herein disclosed, otherwise than as set forth in the claims, but what I claim is 1. In a grinding machine having a grinding wheel and a work slide mounted for reciprocation relative to said grinding wheel, in combination, a Work table swiveled on said work slide and mounted to rock about an axis extending longitudinally of the work, means to support and rotate a piece of work on said work table, and means to rock said work table on said work slide to swing the work toward and from the grinding wheel, said rocking means being operative in all swiveled relations of said table and slide.

2. In a grinding machine having a grinding wheel and.a work slide mounted for reciprocation relative to said grinding wheel, in combination, a work table supported by said work slide and mounted to rock about an axis extending longitudinally of the work,

means to support and rotate a piece of work on said work table, and means movable with said work table effective to rock said work table on said work slide to swing the work toward and from the grinding wheel in-timed relation to the rotation of the work and during reciprocation of said wheel slide.

3. In a grinding machine having a grinding wheel and a work slide mounted for reciprocation relative to said grinding wheel, in

combination, a work table supported by said 1 4. In a grinding machine having a grinding wheel and a work slide mounted for re ciprocation relative to said grinding wheel, in combination, a work table swiveled on said work slide and mounted to rock about an axis extending longitudinally of the work, means to support and rotate a piece of work on said work table, and means to rock said work table on said work slide to swing the work toward and from the grinding wheel, said rocking means being carried by said work table and slide and being moved bodily therewith as said work slide is reciprocated.

5. In a grinding machine having a grinding wheel and a work slide mounted for reciprocation relative to said grinding wheel, in combination, a work table supported by said work slide and mounted to rock about an axis extending longitudinally of the work, means to support and rotate a piece of work on said work table, and means to rock said work table on said work slide to swing the work toward and from the grinding wheel, said rocking means comprising a cam and a cam roll, one of said devices being mounted on the rocking table and the other device being mounted on the wheel slide and means to rotate said cam in timed relation to the rotation of the work.

6. In a grinding machine having a grinding wheel and a work slide mounted for reciprocation relative to said grinding wheel, in combination, a work table swiveled on said work slide and mounted 'to rock about an axis extending lon itudinally of the work, means to support an rotate a piece of work on said work table, means to rock said work table on said work slide to swing the work toward and from the grinding wheel, said" rocking means being operative in all swiveled relations of said table and slide and comprising a rotated cam and acam roll, one of said devices being mounted on the rocking table and the other device being mounted 'on the wheel slide, and a positive driving connection between said cam and the means for supporting and rotatin the work.

In a grinding machine having a grinding wheel and a work slide mounted for reciprocation relative to said grinding wheel, in com bination, a work table supported by said work slide and mounted to rock about an axis extending longitudinally of the work, means to support and rotate a piece of work on said work table, means to rock said work table on said work slide to swin the work toward and from the grinding wheel, said rocking means being operative in all swiveled relations of said table and slide and comprising a rotated cam and a cam roll, one of said devices being mounted on the rocking table and the other device being mounted on the wheel slide, and a change gear drive from said means for supporting and rotating the work to said cam, whereby said cam may be rotated in difierent selected predetermined speed relations to the rotation of the work.

8. In a grinding machine having a grinding wheel and a work slide mounted for reciprocation relative to said grinding wheel, in oombination, a swiveled table mounted for angular adjustment of said work slide, a work table supported by said swivel table and mounted to rock about an axis extending longitudinally of the work, means to support and rotate a piece of work on said work table, and means to rock said work table on said swivel table to swin the work toward and from the grinding wheel, said rocking means being operative in all angular relations of said swivel table and work slide and comprising a rotated cam and a cam roll, one of said devices being mounted on the rocking work table and the other device being mounted on the swivel table. p

9. In a grinding machine, a reciprocating work slide, a swivel table mounted for angular adjustment thereon, a work table mounted to rock on'said swivel table, means to support 

